Automatic real-time file management method and apparatus

ABSTRACT

A method of restoring a file to a previous version of the file, where a current version of the file being available at a local storage location is disclosed. The method includes receiving a request to display a list of captured revisions for a file; displaying a list of captured revisions for said file; receiving a selection from said list indicating a revision of said file to restore; previewing selected revision of said file, wherein said selected revision of said file is received from an Internet storage area network; receiving another selection from said list indicating another revision of said file to restore; previewing selected another revision of said file, wherein said selected another revision of said file is received from a network attached storage location; and restoring selected another revision of said file following the previewing step.

This application is a continuation of U.S. patent application Ser. No.13/925,768 filed Jun. 24, 2013, which is a continuation of U.S. patentapplication Ser. No. 09/957,459 filed Sep. 21, 2001, now U.S. Pat. No.8,473,478, which claims the benefit of U.S. Provisional Application No.60/234,221 filed Sep. 21, 2000, each of which is herein incorporated byreference.

FIELD OF THE INVENTION

This invention relates to file preservation, file capture, filemanagement and file integrity techniques for computing devices.

BACKGROUND OF THE INVENTION

One of the greatest challenges faced by information technology (IT)professionals and computer users today, particularly in the businessenvironment is the protection and management of data. Data may be storedon user workstations, e.g., laptop computers, home or office desktopcomputers, network servers or other devices external to theworkstations. Important data may even be stored on hand-held computingdevices such as PDAs, PALs and other like devices. Complicating theproblem is the fact that the critically of data is increasing and thedifficulty of managing it, protecting it from loss and keeping itavailable is increasing. This is due to a variety of factors,including: 1) the explosion in data volume, particularly that stored ondesktop and laptop computers, 2) the increasing complexity of desktopand laptop computer software and hardware and increasing trends toward apaperless environment were absolute reliance (because paper copies arebecoming less the norm) on data integrity is increasingly significant.

Many home computer users do not realize the vulnerability of theircomputer data. Many that do understand the very real potential for dataloss, purchase backup systems whose operation and user interface isoften confusing and/or time-consuming to use, dramatically decreasingtheir effectiveness or dependability. As a result, many computer usersremain very much at risk of data loss resulting from hardware and/orsoftware failures, fires, stolen equipment, etc. While these risks aresignificant, the most frequent cause of data loss is user error(accidental file deletes, file overwrites, errant programs, etc.), towhich users remain very vulnerable even with most present day backupsystems.

The financial impact of information loss is substantial. As reported bythe Safeware Insurance Agency, in 1999 alone, insurance claims fordamaged, lost and stolen computers (primarily notebook computers)totaled more than $1.9 billion. This figure does not include the untoldbillions lost in intellectual capital and time. It is costly to recreatelost data and there are significant related costs such as lostproductivity and lost opportunity. Consider, for example, the financialand health related impact of a doctor losing all patient contactinformation and medical histories due to a hard disk crash or some othertype of computer failure. In addition, it is costly to keep desktop andlaptop computers up and running in the wake of their increasingcomplexity.

A variety of products have been developed to address data preservationand integrity issues. These products may be loosely grouped into threecategories, manual backup systems, schedule based backup systems andmirroring backup systems.

The least efficient and probably one of the most frequently used backupsystems is the manual backup. At times determined by the user, the userselects files to be hacked up and either utilizes the built in backupprocedure for the corresponding application or manually copies theselected files to a desired backup storage media.

The problems with this method of preserving data are self-evident.Backup procedures are often confusing and may differ from application toapplication. Accordingly, the user must familiarize itself with thevarious methods for performing backups. In addition, users may forget tobackup or elect not to on a given occasion due to time constraints orother reasons. Manual backups often do not allow the user to continue touse the system during the backup procedure. Furthermore, data stored tothe backup media is really only a “snapshot” of the data at the timethat the backup is performed. Any changes made between manual backupswould be lost if there was a failure on the computer's storage device.

Schedule based backup systems typically perform backups according to aschedule either set by the user or preset by the backup software. One ofthe major disadvantages of each type of schedule-based backup system isthat as with manual backups, they miss work done between schedulepoints. This may cause the user to loose critical information as theywork between schedule points. Another disadvantage of schedule-basedbackups systems is that they are frequently confusing and cumbersome forthe user. Still another disadvantage of schedule-based backup systems isthat they function poorly if at all when the backup storage device isunavailable, i.e., they cannot be written to due to a communicationserror or because the device has reached its capacity, is bandwidthlimited, or is non-operational for some other reason.

Mirroring is a technique typically applied to disk based backup systems.Mirroring backup systems are the most comprehensive in that everythingthat happens to the source storage device immediately happens to thebackup storage device. That is the backup drive becomes a mirror imageof the source drive. Accordingly, if a failure occurs on the sourcedisk, processing can be switched to the backup disk with little or noservice interruption.

The strongest advantage of mirroring systems is also their strongestdisadvantage. Because there is no operational discrimination, if a fileis accidentally deleted from the source disk, it is deleted and cannotbe preserved on the backup disk. Likewise, if a virus infects the sourcedisks it is likely to infect the backup disk. Another disadvantage ofmirroring systems is that separate backup disks are required for eachsource disk, doubling the disk requirement for the system. The backupdisk must be at least as large as the source disk and the disks must beconfigured with identical volume mapping. Any extra space that may bepresent on the backup disk is unavailable.

All of these methods require that the user specify whichfiles/directories to back up, but many users have no concept of fliesand directories in their thought process, much less are they able tocorrelate a particular application (e.g. Microsoft Excel) with the kindsand locations of files they generate. These systems simply require toomuch user knowledge, and too much user intervention. The backup user'srisk increases dramatically the lower his computer knowledge may be.

In view of the foregoing, there is a need for a file capture,preservation and management system that captures files just beforeand/or just after they have been changed to minimize loss of databetween backup events. There is also a need for file capture andpreservation system that captures files even when the destinationstorage medium for the files is unavailable. There is a further need fora system that allows users to recover easily and quickly from any typoof information loss, including simple user errors, failed softwareinstallations or updates, hardware failures (attached storage devices),and lost or stolen laptop computers. Users should be able to recover ontheir own, without the intervention of the IT staff, and their backupsystems should be as “behind the scenes” as possible, requiring littleuser attention and extremely small amounts of user computer knowledge.

SUMMARY OF THE INVENTION

It is an object of the invention to a file capture, preservation andmanagement method and apparatus that captures files just before and/orjust after the files are changed.

It is another object of the invention to provide a file capture,preservation and management method and apparatus that has animperceptible impact on system performance from the user's point ofview.

It is a further object of the invention to provide a file capture,preservation and management method and apparatus that captures andstores files even when there is no connection to the desired storagelocation.

Still another object of the invention is to provide a file capture,preservation and management method and apparatus that captures andstores files even when the desired storage location is unavailable.

In accordance with an aspect of the invention, a method for archivingfiles is provided. The method includes, in a computing device, detectingan instruction from a resident program to perform an operation on anoperating file. Upon detection of the instruction, capturing theoperating file temporally proximate to the operation being performed onthe operating file.

In accordance with another aspect of the invention, a method for movingfiles from a first storage location to a second storage location isprovided. The method includes, in a computing device, searching a firststorage location for files responsive to the occurrence of a first eventand moving the files from the first storage location to the secondstorage location responsive to a second event.

In accordance with still another aspect of the invention, a method forarchiving files is provided. The method includes detecting aninstruction from a resident program to perform an operation on anoperating file. The method further includes creating an archive filefrom the operating file and storing the archive file in a first storagelocation temporally proximate to the operation being performed on theoperating file and responsive to detecting the instruction. In keepingwith the method, the first storage location is searched for an archivefile responsive to the occurrence of a first event. The archive file isthen moved from the first storage location to the second storagelocation responsive to a second event.

The accompanying figures show illustrative embodiments of the inventionfrom which these and other of the objectives, novel features andadvantages will be readily apparent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a block diagram of a computing device in accordancewith the present invention.

FIG. 2A is allow chart depicting a process for moving files inaccordance with the present invention.

FIG. 2B is a flow chart showing another process for moving files inaccordance with the invention.

FIG. 3 is a time line illustrating a sequence of events in an exemplaryoperation in accordance with the invention.

FIG. 4 is a time line illustrating a sequence of events in anotherexemplary operation in accordance with the invention.

FIG. 5 is a time line illustrating a sequence of events in still anotherexemplary operation in accordance with the invention.

DETAILED DESCRIPTION OF THE EMBODIMENT Definitions

Operating System (OS)—A computer program that allocates system resourcessuch as memory, disk space, and processor usage and makes it possiblefor the computer to boot up to a human user interface allowing the userto interact with the computer and control its operation.

Operating File—a system or user file.

Archive File—a file containing all of the data of an operating file in anative or altered format and/or a file containing at least some of thedata of an operating file and including references to the location ofthe remainder of the data of the operating file.

Computing Device—a personal computer, a laptop or notebook computer, aserver, a hand-held computing device, a PDA or a PAL. The term computingdevice is not specific to the kind of operating system being run on suchcomputing device, and includes devices running Microsoft operatingsystems, Apple Macintosh operating systems, UNIX operating systems,Linux operating systems, and other operating systems.

Storage Location—any storage device, or a buffer, folder, directory ordesignated area on a storage device.

Personal Attached Storage Device—any internal or external storage deviceconnected to a computing device.

Network Attached Storage Device—any storage device connected directly toa network to which a first computing device is also temporarily orpermanently connected, or any storage device connected to a secondcomputing device that is also temporarily or permanently connected tothe network to which the first computing device is temporarily orpermanently connected.

Internet storage area network—any storage area (device, collection ofdevices, etc.) that can be accessed by the computing device when thecomputing device is temporarily or permanently connected to theInternet.

Peer-to-Peer Storage Device—any storage area (device, collection ofdevices, etc.) that can be accessed by the computing device when it issharing resources with other network or internet accessible computers.

Resident Program—an operating system (OS) or other program that hascontrol over file operations such as “read”, “write”, “save”, “rename”,“delete”, “copy”, “move”, “open”, “close”, etc.

User Program—an application software program or other computing programinstalled by the user or by the computer manufacturer for user creationof desired data, documents, or other information that is designed toenhance the functionality and/or enjoyment and/or usability of thecomputing device. The present invention is directed to an apparatusand/or method for file capture, presentation and management. Theinvention includes a file capture aspect and smart data managementaspect. The invention may be realized as a method and/or an apparatus.More particularly, the invention may be realized as a set of programcode instructions stored on a computer usable medium, a set of programcode instructions embodied in a signal for transmitting computerinformation, and a processor and/or computing device configured asdescribed herein.

FIG. 1 depicts a block diagram in accordance with the present inventioncomprising a computing device 5 including a file capture block 10 (orfile captures), a smart data management block 15 (or smart datamanager), an input buffer 20, output buffer(s) 25, and a database 30. Astorage device 35 is also provided and may be either internal orexternal to computing device 5. The invention functions in conjunctionwith a resident program on computing device 5.

In accordance with an embodiment of the invention, file capture block 10detects an instruction to perform an operation on an operating fileinitiated by the resident program of computing device 5. At a momenttemporally proximate to when the resident program actually performs theoperation, i.e., just before and/or just after the operation isperformed on the operating file, or, more preferably, the instant beforeand/or the instant after the operating file is changed, file captureblock 10 captures the operating file or portions thereof. Preferably,the operating file is captured within a few clock cycles of thedetection of the instruction.

In keeping with a preferred aspect of the invention, file capture block10 causes the location of the captured operating file to be recorded indatabase 30. The continued process of recording information aboutcaptured operating files, or portions thereof, in database 30 creates arecord of each version of the operating file, which may be accessed bythe user or by other programs.

File capture is preferably executed by creating an archive file from theoperating file. The archive file is preferably stored in a temporarystorage location, internal or external to the computer, such as inputbuffer 20. However, the archive file may be stored directly in storagedevice 35. In accordance with a preferred aspect of the invention,storage device 35 may be a personal attached storage device, a networkattached storage device, an Internet storage area network, apeer-to-peer storage device, or other storage device.

In keeping with a preferred aspect of the invention, smart datamanagement block 15 manages the migration of the archive file from theinput buffer 20 through the output buffers 25 to storage device 35. Thismigration may take place either synchronously or asynchronously with thefile capture procedures described herein. The time duration from a filearriving in input buffer 20 and when it arrives on archive storagedevice 35 is managed by the smart data management block 15. Moreparticularly smart data management block 15 regularly examines inputbuffer 20 for the presence of archive files. Smart data management block15 performs this examination upon the occurrence of an event, e.g.,messages from the file capture block 10 and/or various messages from theresident program(s), messages from an input buffer timer sent at timeintervals controlled by a timer or at time intervals selected by theuser. Optionally, smart data management block 15 may then examinedatabase 30 to determine a defined storage location for each of thearchive files stored in input buffer 20. Each archive file stored in theinput buffer 20 may be directed to the same storage location or todifferent storage locations and archive files may be directed tomultiple storage locations for redundancy. Preferably, smart datamanagement block 15 moves the archive files to one or more outputbuffers 25. More preferably each archive file is moved to outputbuffers) 25 corresponding to the final storage location(s) for thatarchive file. Alternatively, all archive files may be moved to a singlecommon output buffer 25 if desired. Upon the occurrence of an event,and/or at defined time intervals, smart data management block 15 movesthe archive files from the output buffers 25 to their respective storagedevice(s) 35. Exemplary events include but are not limited to messagesindicating when storage device 35 is connected and ready for use,messages indicating when storage device 35 is inserted/removed, full,defective, etc., and messages indicating when storage device 35 isdisconnected or unavailable, and messages from a storage device timersent at time intervals controlled by the timer or at time intervalscontrolled by the user. The input buffer timer and the storage devicetimer may operate synchronously or non-synchronously.

Under certain conditions, smart data management block 15 may be unable,or may elect not to move the archive files. For example, if storagedevice 35 is unavailable then smart data management block 15 will notmove the archive files to storage device 35. Among the conditions thatmay cause storage device 35 to be unavailable are i) storage device 35is disconnected from computing device 5, ii) the connection betweenstorage device 35 and computing device 5 is faulty or unacceptably slow,iii) storage device 35 is full, or iv) storage device 35 ismalfunctioning. In addition, smart data management block 15 may alsoregulate movement of archive files according to time schedules set bythe user, by monitoring connection bandwidth availability and movingfiles only during times of high bandwidth availability, or by monitoringother factors Including messages that may received from storage locationserver requests for archive file transmittal.

A preferred operational mode for smart data management block 15 isillustrated in the flowcharts of FIGS. 2A and 2B. In step 100 of FIG.2A, smart data manager 15 examines input buffer 20 to determine whetherany archive files are stored therein. If no archive files are present,smart data manager 15 rests idle until the next event occurs, if archivefiles are detected, in step 105, smart data manager 15 updates database25 to indicate the location of the archive files; that is, to indicatethat the archive files are resident in Input buffer 20. In step 110,smart data manager 15 examines database 30 to determine the properdestination for each archive file. In step 115, smart data manager 15moves the archive files to output buffers 25. In step 120, smart datamanager 15 updates database 30 to indicate that the archive files arenow stored in the output buffer.

In FIG. 2B in step 125, the archive files are moved to one or morestorage devices 30. If smart data manager 15 is unable to move thearchive files to any of the storage devices 30, smart data manager 15rests idle and does not move the archive files until it is notified thatthe storage device is available. Accordingly, the archive files remainin either input buffer 20 or output buffer 25 until smart datamanagement block 15 is notified. In step 130 smart data manager 15updates database 25 to indicate that the archive files are stored in oneor more storage devices 30.

Use Specific to User Program Operations

The following examples are directed to embodiments of the inventionspecific to operations performed by a user program. The file capture,preservation and management processes of the invention are not limitedto execution with the exemplary operation discussed below. The processesof the invention are preferably executed when a resident program causesa change or a change to be imminent in the operating file. Therefore,the following examples are intended to be exemplary only andnon-limiting.

File Capture at File Open

As illustrated in FIG. 3, in step 205, the user or a program selects an“open” operation to open an operating file and an instruction to performthat “open” operation on the operating file is sent to the residentprogram. In step 210, file capture block 10 detects the instruction andcaptures the operating file. Optionally, prior to capturing theoperating file, file capture block 10 may check database 30 to a)determine whether the operating file has previously been archived, b)determine whether the user has selected the operating file forprotection, or c) determine a match to other defined conditions. If thego-ahead conditions exist, then file capture block 10 creates an archivefile and stores the archive file in a storage location such as inputbuffer 20 or storage device 35 just before the resident program opensthe operating file. Preferably, file capture block 10 stores the archivefile in input buffer 20. In step 215 the resident program opens theoperating file and in step 220 the user program displays the operatingfile as originally requested, e.g. Microsoft Word, and makes itavailable for the user to alter, e.g., edit a word processing document,amend or add to a database, etc. Step 210 is performed by momentarilydelaying the execution of step 215 in such a manner as to have little orno perceptible impact on system performance from the users point ofview.

In step 225, the user program begins a process to save the alteredoperating file and an instruction to save the altered operating file issent to the resident program. In step 230 the resident program saves thealtered operating file pursuant to the instruction. In step 235,immediately after the altered operating file is saved by the residentprogram, file capture block 10 captures the altered operating file,preferably by creating and storing an archive file of the alteredoperating file in input buffer 20. In accordance with a preferredfeature of the invention, file capture block 10 may save the archivefile in such a way that previous revisions of the operating file areretained. That is, every time the operating file is changed, filecapture block 10 saves an archive file and database 30 is updated withinformation about the archive file. Accordingly, over time, a pluralityof archive files may be created from the original operating file. Eacharchive file represents a revision of the original operating file.

File Capture in the “RENAME” Operation

As illustrated in FIG. 4, step 305, in performing an operating filerename operation, the user or a program generates an instruction for theresident program to select a new name for an old operating file. In step310, file capture block 10 detects the instruction and captures the oldoperating file. Optionally, prior to capturing the old operating file,file capture block 10 may check database 30 to a) determine whether theoperating file has previously been archived, b) determine whether theuser has selected the operating file for protection, or c) determine amatch to other defined conditions. If the go-ahead conditions exist,then file capture block 10 creates an archive file of the old operatingfile and stores the archive file in a storage location such as storagedevice 35 or, more preferably, input buffer 20 just before the residentprogram renames the old operating file. In step 315 the resident programrenames the old operating file, thus creating a now operating file.Immediately after the old operating file is renamed, file capture block10 captures the new operating file. Optionally, prior to capturing thenew operating file, file capture block 10 may determine whether the newoperating file has previously been archived, whether the user hasselected the new operating file for protection, or other matchingconditions exist. Like the archive file for the old operating file, thearchive file for the new operating file is preferably stored in inputbuffer 20. In step 325 file capture block 10 and smart data managementblock 15 associate or link the new operating file with each of theversions of the old operating file to create a continuous operating filerevision history.

File Capture in the “Delete” Operation

FIG. 5 illustrates the file capture process in the delete operation. Instep 405, the user or a program identifies an operating file to deleteand generates an instruction to the resident program. In step 410, filecapture block 10 detects the instruction and captures the operating fileJust before it is deleted in step 415. Optionally, prior to capturingthe operating file, file capture block 10 may check database 30 to a)determine whether the operating file has previously been archived, b)determine whether the user has selected the operating file forprotection, or c) determine a match to other defined conditions. If thego-ahead conditions exist, then file capture block 10 preferablycaptures the operating file. In step 420, the resident program deletesthe operating file.

As shown by the examples given, a clear advantage of the invention is,regardless of the operation being performed, after each file capturestep, file capture block 10 preferably updates database 30 to indicatethe location of the corresponding archive file. Database 30 may keeptrack of multiple versions of an operating file, any of which may beaccessed at the request of the user or other program.

Another advantage of the invention is that by capturing the operatingfile just before and/or jest after an operation is performed thereon,the invention achieves near real-time operating file archiving whileachieving minimal missed alterations to an operating file.

A further advantage of the invention in its preferred embodiment, isthat by intelligently managing the migration of operating files from theinput buffer 20 through the output buffer 25 to the storage device 35,the invention achieves protection of operating files even when thedesired storage device is permanently or temporarily unavailable.

INDUSTRIAL APPLICABILITY

The present invention is suited for any application that requires orbenefits from near real time file capture, that seeks improved fileintegrity and/or that seeks efficient management of file storage. Forexample, the present invention is particularly useful in backup systems,audit trail systems, computer security systems, systems for monitoringcomputer users and others.

Although the present invention has been described in terms of particularpreferred embodiments, it is not limited to those embodiments.Alternative embodiments, examples, and modifications which would stillbe encompassed by the invention may be made by those skilled in the art,particularly in light of the foregoing teachings.

We claim:
 1. A method of restoring a file to a previous version of the file, a current version of the file being available at a local storage location, comprising the steps of: (A) presenting information for a collection of one or more previous versions of the file, the information for the collection including information indicative of at least one or more of previous versions of the file, wherein a restorable representation of each version, V, of the previous versions, is retrievable from a remote storage location, the restorable representation having at least information required for recovering the version V by a computational machine with the current version being accessible, the remote storage location being accessible through a network; (B) responsive to a selection to preview a selected previous version of the file based on the presented information for the collection of (A), presenting a presentable representation of the selected previous version, the selected previous version being one of the previous versions of the file in the presented information for the collection, the presentable representation having at least information required for presenting at least a portion of the selected previous version by the computation machine with the current version being accessible; and (C) responsive to a selection to restore the selected previous version, retrieving the restorable representation of the selected previous version from the remote storage location and storing the selected previous version by the computational machine as the current version on the local storage location, the selected previous version available from the restorable representation of the selected previous version.
 2. The method of claim 1, wherein, for the presenting of (B), the presentable representation is presented using an application that created the file or the selected previous version.
 3. The method of claim 2, wherein the application is in a read-only mode.
 4. The method of claim 1, wherein the information includes at least two previous versions of the file.
 5. The method of claim 1, wherein the information for the collection includes information indicative of at least one or more of a timestamp, an original file location, and a comment of the previous versions or the file.
 6. The method of claim 1, further comprising the steps of: (B2) after the presenting of (B) and responsive to a selection to not restoring the previous version and responsive to a second selection of a second previous version of the previous versions, version presenting a second presentable representation of the selected second previous version, the second presentable representation having at least information required for presenting at least a portion of the selected previous version; and (C2) responsive to a selection to restore the second selected previous version, retrieving the restorable representation of the second selected previous version from the remote storage location and storing the second selected previous version as the current version on the local storage location, the second selected previous version available from the restorable representation of the second selected previous version.
 7. The method of claim 1, wherein the restorable representation of the selected previous version comprises one or more of a compressed and encrypted version of the selected previous version.
 8. The method of claim 1, wherein the restorable representation of the selected previous version comprises an incremental change to the file.
 9. The method of claim 1, wherein the method has a substantially imperceptible impact on system performance from a user's point of view by delaying one or more operations to prevent a perceptible impact on system performance from a user's point of view.
 10. A method of restoring a file to a previous version of the file, a current version of the file being available at a local storage location, comprising the steps of: (A) presenting information for a collection of one or more previous versions of the file, the information for the collection including information indicative of at least one or more of previous versions of the file, wherein a restorable representation of each version, V, of the previous versions, is retrievable from a remote storage location, the restorable representation having at least information required for recovering the version V, the remote storage location being accessible through a network; (B) responsive to a selection to preview a selected previous version of the file based on the presented information for the collection of (A), presenting a presentable representation of the selected previous version, the selected previous version being one of the previous versions of the file in the presented information for the collection, the presentable representation having at least information required for presenting at least a portion of the selected previous version; (C) responsive to a selection to restore the selected previous version, retrieving the restorable representation of the selected previous version from the remote storage location and storing the selected previous version as the current version on the local storage location, the selected previous version available from the restorable representation of the selected previous version.
 11. The method of claim 10, wherein, for the presenting of (B), the presentable representation is presented using an application that created the file or the selected previous version.
 12. The method of claim 10, wherein the information includes at least two previous versions of the file.
 13. The method of claim 10, wherein the information for the collection includes information indicative of at least one or more of a timestamp, an original file location, and a comment of the previous versions or the file.
 14. The method of claim 10, further comprising the steps of: (B2) after the presenting of (B) and responsive to a selection to not restoring the previous version and responsive to a second selection of a second previous version of the previous versions, version presenting a second presentable representation of the selected second previous version, the second presentable representation having at least information required for presenting at least a portion of the selected previous version; and (C2) responsive to a selection to restore the second selected previous version, retrieving the restorable representation of the second selected previous version from the remote storage location and storing the second selected previous version as the current version on the local storage location, the second selected previous version available from the restorable representation of the second selected previous version.
 15. The method of claim 10, wherein the restorable representation of the selected previous version comprises one or more of a compressed and encrypted version of the selected previous version.
 16. The method of claim 10, wherein the restorable representation of the selected previous version comprises an incremental change to the file.
 17. The method of claim 10, wherein the method has a substantially imperceptible impact on system performance from a user's point of view by delaying one or more operations to prevent a perceptible impact on system performance from a user's point of view.
 18. A method of restoring a file to a previous version of the file, a current version of the file being available at a local storage location, comprising the steps of: (A) iteratively transmitting a representation of at least a portion of a current version of a file to a remote storage location for archiving the current version responsive to a determination of an availability of the remote storage location for accepting a transmission of the representation, the current version being accessible at a computational machine, the remote storage location being accessible through a network; (B) presenting information for a collection of one or more previous versions of the file, the information for the collection including information indicative of at least one or more of previous versions of the file, wherein a restorable representation of each version, V, of the previous versions, is retrievable from the remote storage location, the restorable representation having at least information required for recovering the version V by the computational machine, the remote storage location being accessible through a network; (C) responsive to a selection to preview a selected previous version of the file based on the presented information for the collection of (B), presenting a presentable representation of the selected previous version, the selected previous version being one of the previous versions of the file in the presented information for the collection, the presentable representation having at least information required for presenting at least a portion of the selected previous version by the computation machine with the current version being accessible; and (D) responsive to a selection to restore the selected previous version, retrieving the restorable representation of the selected previous version from the remote storage location and storing the selected previous version by the computational machine as the current version on the local storage location, the selected previous version available from the restorable representation of the selected previous version.
 19. A method of restoring a file to a previous version of the file, a current version of the file being available at a local storage location, comprising the steps of: (a) receiving a request to display a list of captured revisions for a file; (b) displaying a list of captured revisions for said file; (c) receiving a selection from said list indicating a revision of said file to restore; (d) previewing selected revision of said file, wherein said selected revision of said file is received from an Internet storage area network; (e) receiving another selection from said list indicating another revision of said file to restore; (f) previewing selected another revision of said file, wherein said selected another revision of said file is received from a network attached storage location; and (g) restoring selected another revision of said file following said previewing step in (f), optionally, decrypting said selected revision of said file prior to step (d) and decrypting said selected another revision of said file prior to step (f).
 20. The method of claim 19, wherein said method comprises decompressing said selected revision of said file prior to (d) and decompressing said selected another revision of said file prior to (f).
 21. The method of claim 19, further comprising the step of decompressing said selected revision of said file prior to step (d) and decompressing said selected another revision of said file prior to step (f). 